Safety reverse for automatic parking gates

ABSTRACT

An improved automatic drive mechanism for automobile parking lot gates incorporating a reversing mechanism to immediately raise the gate if the gate strikes an object as it is lowering. An electrical interlock prevents the gate from raising when it has reached its final horizontal position.

D United States Patent [151 3,678,622 Miller 1 [451 July 25, 1972 [541SAFETY REVERSE FOR AUTOMATIC 1,934,429 11/1933 Jenkins .L ..49/2sPARKING GATES 2,247,129 6/1941 Little ..49/2s 2,883,182 4 1959 B0 em.....49 28 X [72] Inventor: Hl IOld L. mu", 946 Lakepointe, GIOSSG 3 457; 9 2 u 49: x 48230 3,078,407 2/1963 Schaefer.. .....49/28 x [22]Filed: Aug. 11, 1970 3,129,936 4/1964 Carlson ..49/28 X 3,174,743 3 1965B ..49 28 21 Appl. No.: 62,816 I I Primary Examiner-Dennis L. Taylor 52us. 01 ..49 2a oy Forster & Farley [51] Int. Cl. ..E05! 15/04 [58] Fieldof Search ..49/28, 29, 26, 27 ABSTRACT An improved automatic drivemechanism for automobile [56} Rdmnces Cited parking lot gatesincorporating a reversing mechanism to im- UNITED STATES PATENTSmediately raise the gate if the gate strikes an object as it islowering. An electrical interlock prevents the gate from rais- 1,367,6842/1921 Briggs ..49/28 ing when it has reached its fi l horizontalposition 3,204,170 8/1965 Monks .49/28 X 1,893,824 1/1933 McWhirter..49/28 7 Claims, 4 Drawing Figures Patented July 25, 1972 3,673,622

2 Sheets-Sheet 2 l r 34* l g); (9,

l NVENTOR HAAOIO Z. M/Zlffi ATTORNEYS SAFETY REVERSE FOR AUTOMATICPARKING GATES BACKGROUND OF THE INVENTION Automobile parking lot gateshaving wooden arms that rotate down into a horizontal position blockingthe entrance to or exit from a parking lot are usually operated byticket dispensing, card reading, or vehicle sensing devices in thepavement. In normal operation, the gates raise to permit only onevehicle to pass at a time lowering after the vehicle has passed.However, due to accident or otherwise, a gate may descend when a vehicleis located directly underneath. In such case, the wooden arm strikes thevehicle with damage to both vehicle and gate arm. Sensing deviceslocated underneath and along the length of the wooden arm adapted toreverse the gate are vulnerable to damage along with the gate arm aswhen the parking gate arms are broken off by vehicles driving throughwhen the arm is lowered.

SUMMARY OF THE INVENTION The present invention comprises a pair of crankarms located on the shaft about which the parking gate arm pivots with aspring loaded lost motion connection therebetween. The master crank isrigidly fastened to the shaft and the other slave crank may rotate aboutthe shaft and is pivotally connected at its other end to a connectingrod which in turn is driven by a third crank, transmission andreversible motor. The slave crank may rotate about the shaft onlythrough a few degrees of lost motion with respect to the master crank.This rotation is limited by stops mounted on the master crank. When theslave crank is rotated against one stop, the shaft is then forced toturn with the slave crank and the parking gate arm is raised. Rotationof the slave crank in the other direction is limited by a spring loadedlost motion stop and the parking gate arm is rotated downward. If theparking gate arm strikes an object, the spring is compressed and a limitswitch immediately signals the associated controls to reverse the motorand raise the arm.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the actuatingmechanism,

FIG. 2 is a plan view of the safety mechanism,

FIG. 3 is a side view of the safety mechanism, and

FIG. 4 is a schematic view of the electrical control including thesafety control.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 a shaft is supportedby bearings 12 and is mounted inside a parking gate cabinet 11 shown indotted outline through which one end extends to a flange 13 upon whichthe parking gate arm 15 is mounted. On the shaft are mounted two cams 14and 16 which actuate switches 18 and 20. These switches, 18 and 20,signal the raised and lowered gate arm positions to the control shown inFIG. 4. The shaft 10 is rotated by a safety crank assembly showngenerally by 22 and which in turn is driven by connecting rod 24 towhich the safety crank assembly is pivoted at 26. The connecting rod 24is driven by a crank 25, transmission 28, drive belt 30 and reversibleelectric motor 32.

The safety crank assembly 22 is more particularly shown in FIGS. 2 and3. Welded to the shaft 10 is a master crank 34 which rotates with theshaft and the parking gate arm. Adjacent the master crank 34 is a slavecrank 36 which rotates about a journal bearing 38 mounted on the shaft10. Mounted on the master crank 34 is a stop 40 upon which the slavecrank 36 may abut at 42. A hole 44 is shown in the slave crank 36 forthe pivot 26 also shown in FIG. 1. The slave crank 36 is thus driven bythe connecting rod 24 in FIG. 1, and when the slave crank is drivenagainst the stop 40 at 42 the master crank 34 and shaft 10 are forced torotate with the slave crank 36 and the parking gate arm rotatesupwardly.

A second stop 46 is mounted on the master crank 34 and carries on it aspring member 48 which can contact the slave crank 36 at 50. Uponrotation of the slave crank 36 in the other direction by the connectingrod 24 the slave crank 36 contacts the spring 48 at 50 thus causing themaster crank 34 and shaft 10 to rotate oppositely and lower the parkinggate arm. The spring 48 is sufficiently stiff and preloaded to preventdeflection during normal operation. If, as the parking gate arm islowering, an obstruction is encountered, the shaft 10 and master crank34 will stop and the spring 48 will be deflected against the stillrotating slave crank 36. A switch 52 is mounted on a bracket 54 which inturn is mounted on the master crank 34. The relative movement of theslave crank 36 with respect to the master crank 34 will actuate theswitch and the control shown in FIG. 4 will reverse the electric motor32. The connecting rod 24 will reverse and cause the slave crank 36 torotate oppositely against stop 40 at 42 thereby raising the gate. Theswitch 52 contacts the :slave crank 36 with a spring mounted contact 56which in this case extends to actuate the switch when the spring 48 issufficiently deflected.

In FIG. 4 a control circuit for the safety gate mechanism is shown. Anautomatic or manual operation switch 60 is provided whereby in manualmode the gate will open and remain open. The dashed circuits in theautomatic portion denoted open and close pertain to the circuitsassociated with whatever means are utilized to signal the gate such as aticket dispenser or a vehicle sensing device. In automatic mode and whenthe circuit designated open is actuated, relay R-2 is energized andremains energized thus causing the circuit 62 to be closed and the motor32 to raise the gate. Upon reaching the upper most position, the camoperated switch 20 energizes circuit 64 and de-energizes circuit 66 thusshutting off the motor 32. Circuit 64 energizes relay R-3 disconnectingcircuit 68 at the top. The gate is now ready to lower. Upon completionof the circuit designated close, the relay R-l is energized, the otherportion of the circuit 70 for raising the gate is broken, and thecircuit designated 72 for lowering the gate remains broken. The signalfrom the circuit designated close is only momentary and upon breaking,circuit 72 is completed and the motor 32 operates in the reversedirection to lower the gate until the lower most position is reachedwhereupon the cam actuated switch 18 will break circuit 72.

In the event that an obstruction is encountered by the gate before thelower most position is reached, the switch 52 in the safety crankassembly 22 will be actuated and circuit 74 completed to energize relayR-2. Relay R-2 will break circuit 72 and complete circuit 62 to reversethe motor 32 and raise the gate. The circuit 74 is connected up throughthe cam operated switch 18 to break circuit 74 when the gate is in itslower most position. This is to prevent the gate from being actuated toraise merely by lifting on the end of the arm when it is fully down.

I claim:

1. An automatic parking gate mechanism adapted to raise and lower abarrier gate, a rotatable lost motion drive connection in said mechanismcomprising a driving arm and a driven arm mounted with a common axis ofrotation and a resilient drive means therebetween adapted for deflectionin response to interruption in the downward movement of said gate, andmeans responsive tosaid deflection for raising said gate.

2. The automatic parking gate mechanism of claim 1 including meansresponsive to said gate reaching its normal barrier position fordeactivating said means responsive to said deflection.

3. The automatic parking gate mechanism of claim 1 wherein saidresilient drive means bias said lost motion drive connection to a normalposition which may be overcome by a predetermined resistance to saiddownward movement.

4. An automatic parking gate mechanism having a rotatable shaft, bearingmeans supporting said shaft, a reversible motor driven crank assemblyincluding a reversible motor driven crank means for rotation of saidshaft, and control means actuated by said shaft to limit the angularrotation of said shaft, the improvement comprising; a master crankattached to said shaft, a slave crank adjacent said master crank androtatable about said shaft, said slave crank being pivoted to saidreversible motor driven crank means to thereby rotate said slave crankabout said shaft in either direction, a deflectable stop attached tosaid master crank and engageable with said slave crank whereby uponengagement said master crank and shaft will rotate with said slave crankand lower a parking gate arm and whereby a lowering parking gate armupon striking an obstruction will stop said master crank and shaftthereby deflecting said deflectable stop, safety switch means engageablewith said slave crank and actuated upon deflection of said deflectablestop, said safety switch means being connected to said control means toreverse said motor driven crank means thus raising said parking gatearm.

1. An automatic parking gate mechanism adapted to raise and lower abarrier gate, a rotatable lost motion drive connection in said mechAnismcomprising a driving arm and a driven arm mounted with a common axis ofrotation and a resilient drive means therebetween adapted for deflectionin response to interruption in the downward movement of said gate, andmeans responsive to said deflection for raising said gate.
 2. Theautomatic parking gate mechanism of claim 1 including means responsiveto said gate reaching its normal barrier position for deactivating saidmeans responsive to said deflection.
 3. The automatic parking gatemechanism of claim 1 wherein said resilient drive means bias said lostmotion drive connection to a normal position which may be overcome by apredetermined resistance to said downward movement.
 4. An automaticparking gate mechanism having a rotatable shaft, bearing meanssupporting said shaft, a reversible motor driven crank assemblyincluding a reversible motor driven crank means for rotation of saidshaft, and control means actuated by said shaft to limit the angularrotation of said shaft, the improvement comprising; a master crankattached to said shaft, a slave crank adjacent said master crank androtatable about said shaft, said slave crank being pivoted to saidreversible motor driven crank means to thereby rotate said slave crankabout said shaft in either direction, a deflectable stop attached tosaid master crank and engageable with said slave crank whereby uponengagement said master crank and shaft will rotate with said slave crankand lower a parking gate arm and whereby a lowering parking gate armupon striking an obstruction will stop said master crank and shaftthereby deflecting said deflectable stop, safety switch means engageablewith said slave crank and actuated upon deflection of said deflectablestop, said safety switch means being connected to said control means toreverse said motor driven crank means thus raising said parking gatearm.
 5. The automatic parking gate mechanism of claim 4 wherein saiddeflectable stop includes a spring.
 6. The automatic parking gatemechanism of claim 4 including a stop attached to said master crank andengageable with said slave crank whereby upon engagement said mastercrank and shaft will rotate with said slave crank to raise a parkinggate arm.
 7. The automatic parking gate mechanism of claim 4, includingmeans for deactivating said safety switch means responsive to saidparking gate arm reaching its normal lowered position.